


Hermione Discovers a New Use for the Polyjuice Potion

by Cipi



Series: Hermione Starts a Secret Trend at Hogwarts [1]
Category: Furry (Fandom), Harry Potter - J. K. Rowling
Genre: Cat/Human Hybrids, Furry, Gen, Polyjuice Potion, Secrets, Self-Discovery, Transfiguration (Harry Potter)
Language: English
Status: In-Progress
Published: 2020-06-05
Updated: 2020-06-05
Packaged: 2021-03-03 21:53:28
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,620
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/24552676
Author URL: https://archiveofourown.org/users/Cipi/pseuds/Cipi
Summary: Hermione never forgot her first time, dreams kept coming to her over and over again, taunting her constantly. It invaded her waking moments too, feelings, memories, sensations she wished to experience again. Finally, she gave in, breaking all the rules possible in the process. Will it be everything she remembered? She can only wait to find out and hope she doesn't get caught in the process.
Series: Hermione Starts a Secret Trend at Hogwarts [1]
Series URL: https://archiveofourown.org/series/1774615
Kudos: 8





	Hermione Discovers a New Use for the Polyjuice Potion

**Author's Note:**

> Some details of the technical effects of the Polyjuice Potion have been changed to suit the story.   
> For example: In Harry Potter and the Chamber of Secrets when Hermione attempts to transform into Millicent Bulstrode to accompany Ron and Harry to the Slytherin chambers, she accidentally picks a hair not from Millicent, but from her ginger cat. As a result, she transforms into a humanoid cat. Unlike Ron and Harry, the effects do not wear off after the hour and she is forced to go to the hospital wing and be treated. She does not change back until after winter holidays (if memory serves correctly, they change at Christmas Holidays when the castle is mostly empty, meaning she is in a humanoid-cat form for approximately 2 months).  
> The Polyjuice Potion can last from 10 minutes to 12 hours. For ease of writing and storyline flow, when Hermione brews it this time, it will be identical in steps, procedure, and quality to the first time she did in Chamber of Secrets, lasting an hour. This will ignore the 2-month humanoid factor and means it is a lesser quality potion, allowing her to return to the normal school grounds after an hour, as opposed to being stuck in the bathroom.
> 
> This also turned out WAY longer than I expected for a "first chapter". I hope I can find the motivation to keep writing at all, but I also doubt anyone will notice it to give me that motivation ><
> 
> Forgive any mistakes! My eyes are sore when I'm posting this and I might have missed something!

Hermione woke up from yet another dream. She’d been having them for two years now. She huffed and rolled over in her bed, hearing the soft snores of the other girls in her dorm. She tried to deny the feeling, the exhilaration she felt during those dreams. It had been taunting her for years, daring her to try it again. She closed her eyes tight, but all she could see was the dream repeating.

Hermione drank the potion, a bitter-tasting liquid. She dropped the cup as the feeling overtook her body, it felt like her insides were moving around, like slithering snakes now lived inside her, she was bent over at the waist wondering if she was going to vomit the potion back up. A burning sensation overtook her body, spreading out across her limbs, her body involuntarily straightened, like it was trying to get away from her burning hands and feet. She looked at her hands, her eyes wide. Ginger hair quickly sprouted out whilst simultaneously her entire hand changed shape, into a furry, ginger paw with pink toe beans and claws. She gasped and buckled over again as her entire body sprouted ginger hair and she felt her face moving and changing. She would never be able to describe the feeling with words, but she knew what was happening. She never forgot the feeling from years earlier. As all the burning and weird sensations subsided, she slowly stood up and walked to the nearest basin and mirror. Bright yellow eyes stared back at her, surrounded by ginger fur. Big cat-like ears sat on top of her head, one twitched as she looked at it. She had a little pink nose and whiskers and still mostly human lips. She opened her mouth to see if she could talk, “H-hello,” she cautiously said to herself. She gasped as she noticed the sharpened canine teeth in her mouth and the new bright pink color of her tongue, but at least she could talk. She reached up to her shirt and pulled it out at the neck so she could look down it. Sure enough, ginger fur encased her whole body, as far as she could see. She shifted uncomfortably on her feet before realizing they’d probably changed like her hands. Or should she call them paws? She shook her head as she sat on the floor. She realized she hadn’t considered the most important part of a cat, the tail. She reached behind and brushed it underneath her so she could sit down. She couldn’t believe how fluffy it was, and how soft. She stroked it a few times, jaw hanging open slightly at the sight. She moved her attention back to her feet, quickly pulling off her shoes and ruined socks. The claws had pierced through the cotton material, but thankfully her shoes had survived. Instead of her normal five toes, she now had four toes, each with a soft, pink pad and a sharp claw. The bottom of her foot also had pink pads on them at the heel and the ball of her foot. She stood up, much more comfortable without shoes. She looked in the mirror again and smiled, canine teeth poking through, she did a little spin and discovered she could control her tail, wrapping it around her legs elegantly as she admired herself.

Hermione opened her eyes and sighed again. The dream always ended there, right as she felt the excitement and exhilaration of the change kick in. She loved the feeling and hated it slipping away as she woke up. She lifted her hands up and looked at them, furling and unfurling her boring, human hands. It wasn’t the first time she’d toyed with the idea of making another Polyjuice Potion in secret to test the effects. She knew the second-floor girls’ bathroom was still an abandoned place, occupied only by Moaning Myrtle. She was sure she could do it again… but was it worth the risk? It took approximately one month to make, not to mention the risk of getting ingredients. And she couldn’t ask Harry and Ron to be a distraction against Professor Snape this time, they could never know she enjoyed being a cat. They’d laugh so hard, they’d tell everyone. Perhaps she could ask Harry to borrow his invisibility cloak, she’d just have to say she wanted to get into the restricted library and he wouldn’t push any further. She almost laughed at herself for considering this insane plan. If she really wanted to be a cat, she only had to speak to Professor McGonagall about learning to become an Animagus, something they learned last year in Transfiguration class and was an optional extra for determined students. But deep down, she knew she didn’t want to just be an animal, she liked being a humanoid cat. Still being able to talk and do things, just looking slightly different. Both making the potion and learning to become an Animagus were long and arduous tasks. Both taking a month in time, but the Animagus required specific events and moons to be present and was more prone to having to be restarted over and over again, as well as the chance of a permanent mutation occurring. 

She knew she still had the ingredients and procedure from when she had done it two years ago, she couldn’t justify throwing away something so important, fascinating, and hard to get. She thanked herself for being obsessed with knowledge and decided she’d dig it out later to go over it the needed ingredients and steps. Hermione managed to fall back asleep, with no dreams coming to her this time. She awoke to her dorm room full of the sound of girls getting ready for their day, checking their schedule, and complaining about homework. She laid there for a moment, a feeling of excitement taking hold of her body at what she’s going to attempt to do.

The day passed without incident, although at some points it felt painfully slow. When the evening came around, she retired early to the girls' dorms to go digging around for the piece of parchment. She was sure it was buried deep within the pages of a second year textbook, she kept them all after all. She started pulling out all the books from her second year, flipping through them quickly looking for a loose sheet. It was in the third book, Magical Drafts and Potions, she should have guessed. She rolled it up and tucked it in her pocket, putting all the books back in the proper positions. It hadn’t taken her as long as expected, she could go back down and continue hanging out with Ron, Harry, Neville and the others. But instead, she climbed onto her four-poster bed, shut the curtains around her, and uncurled the parchment on her bed. She quickly scanned through it and then slowly read through it a second time before stopping. She knew it was difficult but she forgot just how difficult it truly was. Two of the ingredients required would have to be stolen from the Professor’s private storage and another two from the potions classroom. Should she try to start gathering ingredients tonight? She needed a full moon to pick the Fluxweed and also the invisibility cloak to be able to sneak into the 6th year Herbology classrooms to get it. And the Lacewing flies needed 21 days to stew. She got up from her bed and peeked out the nearest window, the moon was waning, meaning she’d just missed the full moon. With that, she decided to start with the Lacewing flies, she could stew them whilst waiting for the moon cycle. And in that time she could also gather the other ingredients she needed. 

Hermione went to her trunk and got another piece of parchment paper and a quill and ink, she clambered back into her bed and started writing a list of how she’d do this.

**_1\. Borrow invisibility cloak, go to potions classroom and gather Lacewing flies, Leeches, Horn of Bicorn, and Boomslang skin._ **   
**_2\. Strew Lacewing flies, whilst waiting for the full moon._ **   
**_3\. Borrow invisibility cloak on the full moon, go to year six Herbology classroom, and gather Fluxweed. Go to the Forbidden Forest and gather Knotgrass (same night)._ **   
**_4\. Wait until the following evening and finish potion._ **

She decided she would begin the endeavor tomorrow night, with no Quidditch practice or Astronomy classes allowed on Sunday nights, everyone would be in there respective dorms and chambers by the time she would be deciding to sneak around. She put the parchment papers under her pillow and returned the quill and ink to her trunk. She could hear some voices making their way up the staircase, she jumped back into bed and pulled the curtain shut tight, she didn’t want to be asked what she’d been doing. It took her a long time to fall asleep, but when she did, she didn’t dream much to her surprise. She awoke rested and excited.

Hermione laid in bed trying to come up with a good excuse for when she asked Harry for the cloak. She settled upon saying she would be going to the restricted section of the library to search for a book, The _Book of Spells_. Hopefully, Harry wouldn’t ask questions beyond that, he wasn’t super interested in reading when he didn’t have to. Confident in her idea, she got up and dressed for the day, grabbing a muggle novel before heading down to the common room at 8am. The Great Hall was opened for breakfast on weekends morning for longer than standard school days, so there was no real rush to get there for fear of missing out. House-elves constantly replenished the tables up until the closing time at 10am. She wasn’t surprised to find only a spattering of students in the common room, but of course no Harry or Ron, they loved a good sleep in. She looked over to their usual seating choice. A low, round table surrounded by two armchairs and a two-seater couch, all facing a fireplace. As always, it was empty. Students tended to have their own comfort areas in the common room and that particular table was known as the trios. She walked over there, nodding hellos at the few students around. She curled up in her usual chair, bathing in the warmth of the fireplace whilst she opened up her book and started reading. She didn’t often read muggle books, normally choosing to study and read course-related material. But she always bought a few books from home just in case she had the time or want. After her planning and decision making, she was feeling particularly relaxed and calm and decided it was the perfect time to delve into it.

When 9am rolled around, she was worried the boys were going to sleep through breakfast. She put her book down and stretched, debating if she should ask someone to go wake them or just go down herself and trust that they’d find her. As if on cue, whilst debating the decision, they came strolling down the staircase laughing about something. They spotted Hermione as she stood up and walked over to them. 

“I was worried you were going to sleep through breakfast.” She said, glancing at the clock. 

“Good morning to you, too,” Ron grumbled, forever annoyed at Hermione’s insistent need to be on time to everything.  
  
Harry rolled his eyes at Ron and motioned with his head to the portrait, “Let’s head down, I’m starved.”

They passed through the Fat Lady and made their way down the jumbled staircases to the Great Hall. Bursts of conversation and laughter could be heard echoing through the Hall doors as they approached. The four house tables had random groups of students spread out across them eating and talking. The teachers on duty sat at the head table, looking bored. Professor McGonagall was reading something, occasionally glancing up over her spectacles when a particularly loud noise would occur. At the opposite end of the table was Professor Sprout, who looked to be deeply studying a plant in a pot. Prodding it with her wand, talking to it, and taking notes. 

The trio took their seats, keeping a respectable distance between them and the other groups of students. Hermione sat opposite Ron and Harry, shaking her head as Ron started piling up his plate with a ridiculous amount of food. She wasn’t sure when she should ask Harry, but she was also so excited about the idea that she was almost bursting. She tried to act casual, putting some food on her plate, and eating slowly. 

“Hey Harry, can I ask you a favor?” Hermione almost stopped breathing as she started the conversation.

Harry looked up from his plate, the fork leaving his mouth as he nodded at her, raising his eyebrows. 

She lowered her voice and leaned forward, “I was wondering if I could borrow your cloak tonight, please?” She didn’t add anything extra, hoping by some chance he wouldn’t press her. 

Ron, who hadn’t been watching, but had been listening, choked on his giant mouthful of food, sending several half-chewed pieces flying out across the table and platters.

“Ron!” Hermione screeched in disgust, jolting back on the bench, happily out of spray range. “That’s disgusting!” 

As if on cue, the food before them vanished, replaced by fresh versions of it all. The table was also clean. Hermione smiled, always amazed at the use of magic, but still slightly guilty for the house-elves working so hard below in the kitchen. 

“What do you want the cloak for?” Ron asked after he swallowed the mouthful he had choked on. 

“If you must know,” she said looking at Ron, “there is a book I want from the… restricted section.” She dropped her voice on the last words, not wanting to be overheard by a nosy student or an interested teacher.

“Should have known.” He said, rolling his eyes as he re-stuffed his mouth with strawberry jam coated toast.

Hermione rolled her eyes back at him and refocused on Harry. “So, can I Harry? Please?” She gulped and tried not to look too pitiful in asking. 

“What book do you want from there?” He asked, his plate now pushed aside after Ron’s splattering event.

She kept talking in a low voice, “A _Book of Spells_. That’s the actual title.” She didn’t want to tell them anything about the actual book itself, which was known for casting its own incantations, even real rooms for the person to practice the spells in safely, she couldn’t risk them wanting to come along. “There is a water spell in there I wish to read about for my own interests.” Hermione knew that the spell was taught to sixth years, but she was counting on them not remembering that fact.

“Huh. It sounds kind of boring, but okay, sure. When do you want?” 

“I was thinking of tonight. Students shouldn’t be out because there are no classes or practices on account of it being Sunday, so there should be fewer teachers around as well.”

“Well, you’ll have to go by yourself. Two people underneath it is just too risky.” He looked and sounded apologetic, “Is that okay?”

“It wouldn’t be the first time, I’m pretty sure I can figure it out.” Hermione smiled, happy it was working out as she hoped. 

They lulled into silence at Harry and Ron finished eating, Hermione lost her appetite after Ron’s display, so instead read a few more pages of her novel.

“What do you guys want to do today?” Ron finally said, shoving away his plate, which was somehow miraculously clean.

“Well it’s Sunday, want to go see Hagrid?” Harry put forth. 

Ron and Hermione quickly agreed with the plan. They went back up the dorms, Hermione returned the book to her bedside and the boys grabbed warmer jumpers. Hagrid’s hut was lovely but the wind got in easier than anyone would have liked. They headed down immediately so they’d be back in time for lunch, Ron hated missing a meal. As always they had the best time at Hagrid’s drinking tea, avoiding eating cakes that he baked and getting slobbered on by Fang. All in all, not an unusual visit for the trio to Hagrid. 

Hermione kept wishing for the day to quicker, eager to begin her plan, knowing that she still had to wait so long was painful, but the sooner she started, the sooner she’d feel better about it all. The day passed without further questions, as she guessed, the boys didn’t have much interest in recreational reading, sometimes she had to force them to do the required reading.

After dinner, all the students returned to their common rooms, with a few going to the library. Hermione would be waiting until midnight before slipping away, so she wasn’t worried. Curfew was at 9pm, after all, no students would be out then and very few teachers. They sat around their normal table, the boys playing Wizard’s Chess, a favorite pastime for them both. Hermione was reading again, hoping to make the time pass faster. With 9pm fast approaching, she thought she should get the cloak from Harry to avoid anyone noticing.

“Hey, Harry?”

He barely looked up the chessboard, concentrating on the self-moving figures fighting. “Mmm?”

“Would I be able to grab the uh…” she cleared her throat. “The jumper…” She tried to keep her voice just above a whisper, the common room was fairly crowded.

Harry looked up confused, “Jumper? What?”

Hermione sighed, “You know…” She raised her eyebrows, trying to get him to understand.

“Oh, right.” His attention turned back to the game at hand, instructing his pieces to move against Ron’s. “I’ll give it to you when you’re going, easier that way.”

Hermione just nodded, knowing he wouldn’t even see it, but knowing he was too involved to notice he missed her response. She supposed that was the best plan, she didn’t want someone to notice the weird exchange. Sometimes people kept a closer eye on the trio, especially prefects, thanks to all their past antics. With that, she went back to reading, still trying to make the time go faster. People were slowly starting to drift upstairs to the various dorm rooms. 

“Should we also go?” She asked, “To be less suspicious?”

“Probably. I’ll see you at midnight.” 

“I won’t see you. I’m exhausted from all that winning. Good luck though.” Ron said through a yawn, clearly intending to go straight to sleep.

“You only won because you’ve been playing so much longer!” Harry jabbed back, following him up the boys’ stairs. He threw a wave over his shoulder at Hermione, who just laughed quietly at them. 

She made her way up to her own room, she was too excited and nervous to even be a little bit tired, so at least she didn’t have to worry about falling asleep. She decided to keep reading, her curtains containing most of the light from her candle so as not to disturb the girls who quickly fell asleep around her. She finished her book before it was time to go, bored and worried about somehow falling asleep, she decided to go downstairs early and wait there for Harry. She rolled the parchment paper up that listed the ingredients and shoved it up her sleeve for safekeeping, she didn’t think she’d forget what she was going for, but she had to absolutely certain. She carried her shoes in her hands, her socks padding her footfalls on the hardwood floors. Once downstairs she waited at their normal table and chairs, shrouded in the darkness with some flickering candles lighting up small spots of the common room. 

Hermione didn’t hear anything but saw his feet first. He had some old holey socks on and horrible, red plaid pajamas. She saw the glimmering cloak in his hands and felt a shiver rush through her body at what she was about to do. Breaking the rules and lying to her friends? She hoped it was worth it.

“Do you want me to wait for you here?” Harry asked when he approached her, whispering in the dark. 

“No, if I do happen to get caught, I don’t want them to know you were apart of it.” Hermione stood up, eager to get going. 

“Take it off and hide it wherever you can if you do get caught, otherwise it will get confiscated and… you know.” Harry didn’t need to finish what he was saying. It was his Dad’s cloak and it held more value than anything else he owned for that reason and was also very rare and handy. 

“I will, Harry. I appreciate you letting me use it at all.” Hermione smiled at him, feeling guilty for all the lying she was doing in pursuit of her own selfish reasons.

He didn’t say anything but held out the cloak with one hand. “Make sure you put it on the right way.” He said with a smirk. 

“I think I can figure it out,” Hermione said with a quiet giggle. Go back up to bed before I leave, just in case.” 

Harry nodded and waved on his way back up the boys’ stairs. She slipped her shoes back on her feet, wrapped the cloak around her shoulders for ease of carrying and use, and left the common room through the portrait hole. She traveled quickly and quietly down the temperamental stairs, keeping her wand unlit for the most part. If you disturbed the wrong portrait at night the occupant was likely to alert Filch or another teacher. And the ghosts also prided themselves on alerting staff about out of bed students. 

It took Hermione half an hour to make her way down to the dungeons where the Potions classroom was. She thankfully didn’t run into any teachers, but at one point she did hear Filch and Mrs. Norris at the end of the corridor she’d just been in. She was thankful she’d decided not to have her wand lit for most of the trip or that could have been the end of it. The classrooms stayed unlocked round the clock. There was generally no need to lock them unless there was a special event or they were forbidden for one reason or another. 

She entered through the big wooden door, for something so old, she was surprised at how quiet it was. She shut it behind herself, hoping to hide the light from her wand that she’d need to find what she was here for. She uneasily adjusted the hood around her neck. It wasn’t a conventional cloak with strings and a hood since it was designed to be laid over the entire body. So she’d tied two corners around her neck so she didn’t accidentally drop it and was at least partially hidden for her trip. Feeling mostly safe down in the dungeon classroom, she untied it from her neck and placed it on a desk. She paused and picked it back up, she needed to go into Professor Snape’s private office, and she didn’t want to leave the cloak in the open in case she needed it.

She laid the cloak over her arm and walked up to the office door. Not to her surprise, the door was locked was a Locking Spell. Professor Snape was a suspicious sort. She used her wand to cast the unlocking spell, hearing the click, she gently pushed open the door, sticking her head through to check it was empty, before pushing it open wide enough for her whole body. She once again shut the door behind her, placing the cloak down on the Professor’s desk. She looked around for the supply cabinet that held the restricted items. As expected it was locked, but this time with a tough-looking padlock, although not for long. She cursed herself for forgetting to bring some sort of bag for the items she was getting and hoped she’d be able to fit them in her pockets. 

She pulled the list from her sleeve, Horn of Bicorn and Boomslang skin were the two things in the restricted supply closet. She found them quickly, turned out Professor Snape was very neat and labeled everything in alphabetical order. Thankfully, both fit in her pockets, if a little awkwardly. She re-locked the padlock and pulled it to check it was properly shut, she then grabbed the cloak off of the desk, stopping before the door to listen for any noises. Being met with complete silence, she opened the door slowly, sticking her head out again before following with her body. She shut the door gently behind her and cast the Locking Spell on the door, giving it a shove to check it was shut properly.

With that done, she turned back to the classroom. Lacewing flies and Leeches were the last things she could get from here, they were kept in the school supply closet, being an unrestricted item used in multiple spells. She cursed herself again for not thinking about how she would transport the icky things and opted for having to steal two of the small glasses jars. They were haphazardly kept in piles of various sizes against the giant, slimy cement wall of the dungeon, she doubted Professor Snape would notice them missing. She grabbed two from a very unsteady pile and walked over to the supply closet. It was a little more chaotic thanks to students not caring about order or neatness, but once again she found what she needed with speed. 6 leeches and 6 scoops of Lacewing flies were quickly packed into the small glass jars. She had collected extra in case something happened. She didn’t want to have to make this trip again.

The jars wouldn’t fit in her pockets, so she tucked her jumper into her pants for a very distinguished look and dropped them down the neck. She didn’t want to risk dropping either of them, the noise of them breaking alone would give her away and she wouldn’t be able to clean the mess up in time. She put the cloak on properly this time and kept one arm securely under where the jars sat, just in case her jumped moved whilst she was sneaking along. 

She made it through the portrait and back to her bed mostly without incident. The trip back took the same time, with the only mishap being when the jars moved and clinked loudly against each other, causing several portraits to stir and mutter in their sleep. She stood next to her bed, silently taking off the cloak and her shoes. She carefully removed the jars from her jumper, placing them on the bed along with the Horn of Bicorn and Boomslang skin. She grabbed a pair of socks and shoved one jar in each to avoid another clinking accident before placing all the items in a spare pillowcase which she shoved under her bed up against the wall. She grabbed a jacket she hardly ever wore and draped it over, to make it look like a pile of clothes in case someone went snooping. The blankets hung all the way down to the floor from the bed, so she was sure it would go unnoticed for now. She put the cloak under her pillow so she’d remember to give it to Harry tomorrow.

She finally undressed and climbed into bed, a stupid smile covering her face. She couldn’t believe she’d done it, she was more excited than she’d been over anything before, her plan was coming together nicely. She yawned and fell asleep quickly, no dreams haunting her tonight.

**Author's Note:**

> Thanks for reading, if you made it this far that is!


End file.
